Instrument cluster repair - Electronics tech

[dickfoster]

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OK, this is almost embarrassing how easily it can be repaired. The hour meter is an off the shelf componant that is used all ovr. The display is held on with tabs. No soldering at all.

It's probably connected with what is called zebra strip. It's made of alternating layers of conductive and non conductive rubber strips that is squeezed between two lines of contacts one on the board and the other on the back of the glass LCD so alignment between the two is critical. Usually there is some sort of mechanical alignment aid in the design of the parts.

 

[rockyridgefarm]

Thanks! With that in mind, my son and I tried another tack at getting it. We were able to get a proper display! While it won't go back together permanently; we were able to get the exact number of hours. I have two possibilities for replacing the hour meter set to that number! I have one clocking up (slowly) and will see if the programmable one will be a direct fit. One, or the other, will have it good as new.,

 

[Kyle_in_Tex]

Keep us posted. What did you actually do to get it showing?

 

[rockyridgefarm]

738.6

 

[rockyridgefarm]

We were able to read the old hourmeter using a new LCD; just couldn't get it to stay put. So, I ended up connecting a new meter to a 12v battery and just let it run. Slowly, but surely, it got the right hours!

 

[texasranger556]

Very nice! I'll definitely keep this in mind if I run into a bad LCD on mine. Thanks for the update!

 

[Tedhamill]

Rocky ridge farm- I am in desperate need of your help I stumbled across your post about fixing the digital hour meter on your John Deere.i have a John Deere 6403 2003 model.the hour meter went out on me and have been searching high and low to find a way to fix it without having to buy a new one that will be set to zero.mine lights up but doesn't show enough of the numbers to tell how many hours it has but every once in awhile you will look down and it wok be working but will go back to not working a few minutes later.i saw the picture of the one you bought as a replacement and it is identical to mine.how did you get it set to the right hours?my tractor currently has 1683 hrs as it worked yesterday for a whole 2 minutes.but who knows when it will decide to work again.if you could help me I would be truly grateful.

 

[DLTTrekkers]

 

[DLTTrekkers]

Remove that fuse and see if its working ?

 

[Tedhamill]

Dlt trekkers I will try that.i have checked for blown fuses and shorts and have it been able to locate any reasons so figure my LCD screen is bad.what does that fuse go to?

 

[DLTTrekkers]

Put the cluster in diacnostic mode

 

[Tedhamill]

Tried removing fuse but is still doing same thing.shows pieces of the numbers but not enough to read.rocky ridge could you tell me how you got yours set to the right hours because if that's what's wrong I'd like to get the. New LCD ordered so I can get it fixed

 

[texasranger556]

I think he ended up hooking his new hour meter to a battery for a month or two until it hit the 700 hours.

 

[rockyridgefarm]

Exactly! As I already PM'd, I couldn't get a reliable connection swapping a new LCD panel on the old module, so we hooked a new module to a battery and let it clock up. My buddy who is a Helicopter tech told me they've attached drill motors to mechanical ones to run them up. It happens.

Hope that you get it!

 

[dfkrug]

It's probably connected with what is called zebra strip. It's made of alternating layers of
conductive and non conductive rubber strips that is squeezed between two lines of contacts one on the board and the
other on the back of the glass LCD so alignment between the two is critical. Usually there is some sort of mechanical
alignment aid in the design of the parts.

I did not know that strip had a name. I have had them fail in numerous devices. They need just enough
mechanically-applied pressure to get a good contact.

On one of my 4300s, I tried to get the zebra strip to contact better, without luck. At the time I was not
aware of any replacement of just the hour meter, so I installed a separate electro-mechanical one. I prob
should have run it independently 24/7 for a while to get it up to the correct #, as Mike did. (Nice work, Mike.)

 

[rockyridgefarm]

IT was nice, for a while. Then it mysteriously reset to zero. It makes no sense why. I am adding a vibration typpe external one to act as a backup. Just in case.